POSIX says that localtime should fail with EOVERFLOW if the result
cannot be represented, which is the case for most large (in absolute
value) time_t inputs, since they overflow (or underflow) tm_year, which
is an int. This patch introduces this functionality. Previously, tm_year
just overflowed (or underflowed) silently.
Incidentally, this partially fixes#12729 without solving the root
problem, which is that time_to_tm is linear in its input to determine
the number of years since epoch.
This means that the bash port mktime test no longer times-out in 60s,
but it still fails (faster) in some other place. Due to underlying issue
in the algorithm, the worst case inputs still take a couple of seconds
on my machine.
POSIX describes WCHAR_MIN and WCHAR_MAX in stdint.h(0P), while
wchar.h(0P) only says "as described in stdint.h".
As there isn't a trivial path of "may make visible", just move it to a
shared header and include it from both files.
On x86-64, `int64_t` is defined to be `long` (not `long long`) , so for
printing, the "l" format specifier has to be used instead of i686's
"ll".
A couple of these macros weren't updated when the x86-64 target was
added, so using them produced warnings like this:
> warning: format specifies type 'long long' but the argument has type
> 'int64_t' (aka 'long') [-Wformat]
>
> "DW_CFA_GNU_negative_offset_extended(%" PRId64 ")\n", offset);
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~
This commit changes the macros to be correct for both architectures, and
reorders them to be consistent and adds a couple missing ones for the
sake of completeness.
If we break out of the loop before we attempt to allocate again,
then we double free the memory pointed to by `name_path`.
Found by Static Analysis: Sonar Cloud
Instead, to determine these values (both the pts name and tty name), use
other methods. For determining the new name of the allocated psuedo
terminal, use ioctl on a file descriptor we got after opening /dev/ptmx
with the TIOCGPTN option.
For determining the name of TTY, we enumerate both /dev/pts and /dev
directories to find matching inode number and matching device mode.
This ioctl operation will allow userspace to determine the index number
of a MasterPTY after opening /dev/ptmx and actually getting an internal
file descriptor of MasterPTY.
Day and month name constants are defined in numerous places. This
pulls them together into a single place and eliminates the
duplication. It also ensures they are `constexpr`.
Ports / other userland often needs such an implementation to function.
Lets expose `AK::timing_safe_compare` under the same name used used in
OpenBSD / FreeBSD / Solaris and other projects.
This causes problems in code of the form
if (/* condition */)
FD_ZERO(&thing);
else
do_other_thing();
Wrapping the call to memset() in a do/while block fixes the issue.
I also added a common interface with StringView compatible parameters:
int serenity_setenv(const char*, ssize_t, const char*, ssize_t, int)
This function is called by both C and C++ API for setenv().
Just like Dr. POSIX ordered. Move the macro where it belongs, but make
sure it's visible to Userland files compiled with -DKERNEL. Parts of
LibEDID that are compiled into the Kernel use offsetof to parse the
EDID information given to us by hardware.
POSIX doesn't tell us to export a macro like this, and it's largely
going to never be defined when compiling a serenity-native C++ file,
since AK defines it already.
This does raise a strange issue where some futex-related helpers in
serenity.h are declared with ALWAYS_INLINE. Whether these helpers belong
in a C-visible header as file-static methods is questionable, but let's
work around the issue but adding some preprocessor magic to make sure
these declarations get the behavior they used to have without leaking
macros.
Arguments larger than 32bit need to be passed as a pointer on a 32bit
architectures. sys$profiling_enable has u64 event_mask argument,
which means that it needs to be passed as an pointer. Previously upper
32bits were filled by garbage.
gethostbyname() and gethostbyaddr() now set h_errno (per spec) and try
to recover and return (with an error) instead of choking in VERIFY()
whenever an I/O or protocol error occurs in the communication with
LookupServer.
The DT_RELR relocation is a relatively new relocation encoding designed
to achieve space-efficient relative relocations in PIE programs.
The description of the format is available here:
https://groups.google.com/g/generic-abi/c/bX460iggiKg/m/Pi9aSwwABgAJ
It works by using a bitmap to store the offsets which need to be
relocated. Even entries are *address* entries: they contain an address
(relative to the base of the executable) which needs to be relocated.
Subsequent even entries are *bitmap* entries: "1" bits encode offsets
(in word size increments) relative to the last address entry which need
to be relocated.
This is in contrast to the REL/RELA format, where each entry takes up
2/3 machine words. Certain kinds of relocations store useful data in
that space (like the name of the referenced symbol), so not everything
can be encoded in this format. But as position-independent executables
and shared libraries tend to have a lot of relative relocations, a
specialized encoding for them absolutely makes sense.
The authors of the format suggest an overall 5-20% reduction in the file
size of various programs. Due to our extensive use of dynamic linking
and us not stripping debug info, relative relocations don't make up such
a large portion of the binary's size, so the measurements will tend to
skew to the lower side of the spectrum.
The following measurements were made with the x86-64 Clang toolchain:
- The kernel contains 290989 relocations. Enabling RELR decreased its
size from 30 MiB to 23 MiB.
- LibUnicodeData contains 190262 relocations, almost all of them
relative. Its file size changed from 17 MiB to 13 MiB.
- /bin/WebContent contains 1300 relocations, 66% of which are relative
relocations. With RELR, its size changed from 832 KiB to 812 KiB.
This change was inspired by the following blog post:
https://maskray.me/blog/2021-10-31-relative-relocations-and-relr
The global variable use in these functions is super thread-unsafe and
means that any concurrent calls to sprintf or fprintf in a process
could race with each other and end up writing unexpected results.
We can just replace the function + global variable with a lambda that
captures the relevant argument when calling printf_internal instead.
I tried the OpenSSH port but it failed to compile due to a missing
definition of this macro. It's simple enough to add, and it's addition
allowed OpenSSH to compile once again.
I also went ahead and added spec comments for these macros as well.